I too would like to be able to design a ride in Google maps and download it to my iphone, but I am still working on finding a solution. I have Motion-X Drive which won't do it, but as posted earlier Motion-X non Drive version is supposed to. I haven't tried that app yet, but it doesn't seem to be made for road usage from looking at it. Please correct me if I am wrong.
As far as a mount goes, I just bought this mount
and will be using it for a 2000 mile trip next week. Hopefully it will be good. It was made for mountain biking, so hopefully it will stand up to my paint shaker on the road.
We'll see. If I fry my iPhone, I guess I'll just have to get a 5